Arthritis in Dogs: Do the Drugs Really Work?

Arthritis is, unfortunately, a fact of life. The syndrome occurs most frequently in middle-aged and older individuals of many species, including dogs, cats, and humans.

The most common form of arthritis in dogs is degenerative joint disease, or DJD. As the tissues in joints deteriorate, the joints lose their flexibility and can be painful or stiff, especially after a period of inactivity. The symptoms are most common in the morning and may be exacerbated by cold weather. Heavy activity one day can cause a flare-up the next.

The condition is nearly universal in the hips of older, larger dogs, but dogs of all sizes can suffer arthritis in just about any mobile joint.

Limping is the most common symptom in dogs, but some show more subtle symptoms, such as decreased interest in walking, or reluctance to jump or climb stairs or hills.

Over time, dog arthritis can lead to serious mobility problems that can compromise quality of life. Unfortunately, intractable pain and immobility are leading causes of euthanasia, especially in larger dogs. Because arthritis is so common, drugs to treat the condition are among the most frequently prescribed in veterinary medicine.

But do these drugs really work? And are they safe? The short answer to both these questions is "Usually, but not always."

The most commonly prescribed arthritis medications all are within a class of drugs called nonsteroidal anti-inflammatory drugs, or NSAIDs. They include aspirin, meloxicam (Metacam), carprofen (Rimadyl or Novox), firocoxib (Previcox), deracoxib (Deramaxx), and etodolac (Etogesic). The manufacturers' drug reps relentlessly try to outdo one another to convince vets and staff that their respective drug is the best.

This often involves bribes of pizzas. If the Merial rep bought two pepperoni pizzas for the staff, the Pfizer rep may become extragenerous and buy two supremes. Therefore, Rimadyl must be superior to Previcox, right? (Tragically, these pathetic bribes often work in veterinary offices. Human physicians usually hold out for -- and sometimes receive -- golf junkets in the Caribbean.)

I kid, of course, but the fact is all of the NSAIDs work in essentially the same way. And all of them, including humble aspirin, can cause the same side effects. Despite drug rep claims, none has been proven to be the most effective -- or the safest. Period.

Some are stronger than others. Aspirin is relatively weak. Carprofen is medium-strength. Firocoxib is strong. Generally speaking, the risk of side effects is proportional to the strength of the drug. However, every individual dog will react in a unique fashion to every different NSAID.

Let's talk about those side effects. Simple gastrointestinal upset is the most common, but all can cause liver or kidney damage and gastrointestinal ulcers. In the worst cases, which are very rare, they can cause liver failure, kidney failure, or fatal perforating gastrointestinal ulcers.

To give you a sense of how rare life-threatening NSAID complications are, I will tell you that no dog has ever suffered a life-threatening complication from an NSAID prescription I have issued. But I'm not a heavy prescriber (I prefer other treatments -- see below -- as a first step). However, I work at an emergency hospital, and I have seen a few dogs die from reactions to NSAIDs prescribed elsewhere.

That number pales in comparison to thousands of dogs I've seen whose lives have been improved, often dramatically, by the drugs. When used appropriately, they are often a reasonable choice for treatment of arthritis -- but they are not the only choice. And they shouldn't necessarily be the first choice, since there are several other ways to help.

Weight management is absolutely the most effective and safest arthritis therapy. Extra weight causes severe strain on joints, so overweight dogs with poor mobility often become highly mobile once they lose the excess weight. Basic physical therapy, such as range-of-motion exercises, massage, and especially muscle strengthening exercises, also benefit dogs with arthritis. Talk to your vet about a weight management and a physical therapy program.

Supplements such as glucosamine and omega-3s (fish oil) are controversial (the evidence on these products is spotty), but many owners feel they help. Be aware that glucosamine might be linked to liver damage. Stem cell therapy has recently become available as an (expensive) treatment, but not all vets are convinced it's effective. Laser therapy is also now touted as a treatment, but once again, some vets worry that while it has proven to be profitable, it has yet to be proven to be effective.

Finally, straight-up painkillers such as tramadol may help, particularly during flare-up situations.

Arthritis medications do generally work in dogs, but they are not panaceas. Owners of arthritic dogs should not simply reach for a bottle of pills, but should instead consult with their vet to develop a comprehensive management plan.